Mass spectrometry (MS) combined with gas chromatography (GC) is the most powerful technique available for identifying bioactive compounds and for the selective detection of drug metabolites. Recent developments in GC introduced by high resolution capillary columns have outstripped the ability of conventional MS to maintain the integrity of chromatographic information during analysis. Time-array detection (TAD) for time-of-flight mass spectrometry (TOFMS) appears to be the solution to this problem. This Phase II application proposes to interface the integrating transient recorder developed in Phase I to a novel time-of-flight mass spectrometer designed to accommodate TAD, yielding a commercially viable GC/TOFMS/TAD system capable of exceptionally high speed and sensitivity at a reasonable cost. This novel instrument will accommodate not only high resolution capillary column GC, but also enable the new technologies of fast chromatography and Time-Compressed Chromatography TM. These new capabilities will allow biomedical and clinical analysis times to be dramatically reduced while maintaining or improving analytical sensitivity.